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2021/12/7忙了一晚上的李师傅，才发现MySQL 1045 原来是 密码错误（裂开）

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安装过程参考主页文章

解决Navicat 连接Mysql报2059错误

报错内容发生在Windows下的Navicat

下面是解决步骤：

报错原因 ：

MySQL 8  之前的版本中加密规则是mysql_native_password,而在mysql8之后,加密规则是caching_sha2_password

解决方法：改加密规则
Win+R Input :  cmd    Enter
//login MySQL
Input :  mysql -uroot -p123321a
//Select Databas  
Input :    use mysql;
Input :    ALTER USER 'root'@'localhost' IDENTIFIED BY '123321' PASSWORD EXPIRE NEVER;    #更改加密方式
Input :    ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY '123321';   #更新用户密码
Input :    FLUSH PRIVILEGES;   #刷新权限

# 远程连接请将'localhost'换成'%'
    mysql -u root -p
mysql>use mysql;
mysql>select 'host' from user where user='root';
mysql>update user set host='%' where user='root';
mysql>flush privileges;
mysql>select 'host' from user where user='root';
运行完毕后再次连接测试，若还不行重启mysql服务，或是直接重启服务器

过程中使用的弱密码不针对实际环境，生产环节请不要使用弱密码！！！

针对新安装的MySQL密码问题：

leeyangy@leeyangy:~$ mysql -u root -p
Enter password: 
ERROR 1698 (28000): Access denied for user 'root'@'localhost'

sudo vim /etc/mysql/mysql.conf.d/mysqld.cnf, 进入到这个配置文件，然后在这个配置文件中的 [mysqld] 这一块中加入 skip-grant-tables 这句话

重启MySQL服务 service mysql restart

use mysql;   然后敲回车
update user set authentication_string=password("123321") where user="root";  然后敲回车
flush privileges;  然后敲回车

退出数据库 注释掉skip-grant-tables

leeyangy@leeyangy:~$ mysql -u root -p
Enter password: 
ERROR 1524 (HY000): Plugin 'auth_socket' is not loaded

此时还是报错？再去取消注释 skip-grant-tables

mysql -u root -p 直接回车再回车
use mysql;
mysql> select user, plugin from user;
+------------------+-----------------------+
| user             | plugin                |
+------------------+-----------------------+
| root             | auth_socket           |
| mysql.session    | mysql_native_password |
| mysql.sys        | mysql_native_password |
| debian-sys-maint | mysql_native_password |
+------------------+-----------------------+
4 rows in set (0.00 sec)

查询到上面这样的信息

从表中可以看到在执行了select user, plugin from user;后，错误原因是因为plugin root的字段是auth_socket，改掉它，替换为mysql_native_password就行了。输入：

update user set authentication_string=password("123321"),plugin='mysql_native_password' where user='root';

再次查询

mysql> update user set authentication_string=password("123321"),plugin='mysql_native_password' where user='root';
Query OK, 1 row affected, 1 warning (0.00 sec)
Rows matched: 1  Changed: 1  Warnings: 1

mysql> select user,plugin from user;
+------------------+-----------------------+
| user             | plugin                |
+------------------+-----------------------+
| root             | mysql_native_password |
| mysql.session    | mysql_native_password |
| mysql.sys        | mysql_native_password |
| debian-sys-maint | mysql_native_password |
+------------------+-----------------------+
4 rows in set (0.00 sec)

root用户的字段改成功了！

下面是卸载过程：

    1.首先查询依赖：    dpkg --list|grep mysql

    阿巴阿吧阿巴的列出信息

    .........................................................................................................

root@ubuntu:/home/ubuntu# dpkg --list|grep mysql

    ii mysql-client-core-8.0 8.0.23-0ubuntu0.20.04.1 arm64 MySQL database core client binaries
    rc mysql-common 5.8+1.0.5ubuntu2 all MySQL database common files, e.g. /etc/mysql/my.cnf
    rc mysql-server-8.0 8.0.23-0ubuntu0.20.04.1 arm64 MySQL database server binaries and system database setup
    ii mysql-server-core-8.0 8.0.23-0ubuntu0.20.04.1 arm64 MySQL database server binaries

    2. 借用root 卸载 ：  

root@ubuntu:/home/ubuntu#sudo apt-get remove mysql-common

        从上面依赖关系中看到我当前安装的MySQL版本是8.0

        执行命令 sudo apt-get autoremove --purge mysql-server-8.0

        以下是输出log--由于使用不同版本linux 此处信息仅供参考

root@ubuntu:/home/ubuntu# sudo apt-get autoremove --purge mysql-server-8.0
Reading package lists... Done
        Building dependency tree
        Reading state information... Done
        Package 'mysql-server-8.0' is not installed, so not removed
        The following packages will be REMOVED:
        libcgi-fast-perl* libcgi-pm-perl* libencode-locale-perl* libevent-core-2.1-7* libevent-pthreads-2.1-7* libfcgi-perl*
        libhtml-parser-perl* libhtml-tagset-perl* libhtml-template-perl* libhttp-date-perl* libhttp-message-perl*
        libio-html-perl* liblwp-mediatypes-perl* libmecab2* libtimedate-perl* liburi-perl* mecab-ipadic* mecab-ipadic-utf8*
        mecab-utils* mysql-client-core-8.0* mysql-server-core-8.0*
        0 upgraded, 0 newly installed, 21 to remove and 0 not upgraded.
        After this operation, 294 MB disk space will be freed.
        Do you want to continue? [Y/n] y
        (Reading database ... 99869 files and directories currently installed.)

        .......................................这里省略了...................................................................

        3.清理残余文件

       dpkg -l|grep ^rc|awk '{print$2}'|sudo xargs dpkg -P

        4.再次查看还有没有剩余依赖 

dpkg --list|grep mysql

        如果查询结果为空，则结束卸载。

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